WordPress' flexibility and ease of use convinced two organizations to use it as their content management system.

In this last installment of our three-part series on finding the best open-source content management system (CMS) for your needs, we asked two organizations -- online magazine Quartz.com and Carleton University -- to talk about why they chose WordPress over other open-source options and how well that decision has stood the test of time. (Our first installment examined Drupal and the second looked at Joomla.)

WordPress got its start as a blogging platform in May 2003 and gradually evolved, first into a blogging system that let users add Web pages outside of the blog and then into a full-featured, popular CMS. Of the three most popular open-source CMSs -- WordPress, Joomla and Drupal -- WordPress is both the most popular and the fastest growing by far, according to Web technology tracker W3Techs.

"Drupal has long provided a flexible platform, enabling it to meet a broad set of needs. However, WordPress 3.0 significantly bridged the flexibility gap," says Larry Cannell, an analyst with Gartner.

Unlike Drupal, WordPress has a reputation for being notoriously easy to use -- in part because you don't have to download the software from the WordPress.org site and build your own Linux, Apache, MySQL and PHP setup if you don't want to. Many less technically savvy people use the WordPress.com hosting service, which makes getting started easy.

This also means that companies using the higher-end WordPress CMS will find that many employees are already familiar with WordPress' administrative interface.

While Joomla and Drupal have more of a committee-based approach to decision-making as far as the direction and development of the software is concerned, the WordPress community is more hierarchical, which can mean faster decisions. "We have the benevolent dictator for life model," says co-founder Matt Mullenweg. "Ultimately, the buck stops at me."

WordPress: Pros, cons and what's coming

Pros: WordPress is widely considered to be the easiest CMS for the nontechnical user and offers more than 21,000 plug-ins. "People come to WordPress when they want to do something quickly and when they want it to be easy to maintain," says Matt Mullenweg, co-founder of WordPress and founder of Automattic, which operates the website hosting service WordPress.com.

Cons: The way in which WordPress handles multimedia could use improvement. "Right now I think it's too hard," Mullenweg says. Over the next year, he says, developers will be working to make that easier.

The WordPress community is also working to improve social integration, particularly with Facebook and Twitter, and to support mobile apps. Right now, Mullenweg says, "If you're a brand-new user signing up for a WordPress website from a mobile device, the process could be a lot smoother."

What's coming: Over the years, WordPress has evolved from a simple blogging platform to a CMS. As people use the platform to build more complex websites, it is now evolving into an app engine, says Mullenweg. "It will be more like a development environment like Django or Rails. It's already happening for advanced developers."

Today, he says, it's possible to use WordPress as a back end for mobile apps and not even have a website.